Christchurch's transportation plan could take 20 years to fully implement.

Public submissions on the proposed plan can be made until February 1.

Public meetings and workshops are being organised to help people make submissions.

"To give this life could take a couple of decades," Christchurch Central Development Unit (CCDU) director Warwick Isaacs said.

"Within five years there'll be significant change but where it gets further out and starts inter-connecting with the [rest of the] city comes down to funding. A lot of it will be [Christchurch city] council led."

The CCDU has to deliver the final plan to Cabinet in March.

Only then will its cost be properly considered.

Isaacs will only admit to having a "broad idea" of the price tag.

"Until we get to the end of the consultation, we don't know what we'll be able to report back to the Cabinet ministers. We're not talking cost in here.

"This is a vision, rather than a full-funded plan."

When the bill is added up, the cost will be shared among many of the parties that worked on the plan.

The Canterbury Earthquake Recovery Authority, which includes the CCDU, will take care of a "recovery portion", as it already does with some infrastructure costs. That money comes from central government.

The NZ Transport Agency, another key contributor to the plan, has some roading responsibility and Environment Canterbury and the Christchurch City Council will pay for some roading and public transport. Some of that money will come from already allocated transport budgets.